I adopt representing 3 with thumb, index, and middle finger (German?), Instead of the usual index, middle, ring. This is easier for teaching my little girl as her hands muscle aren't fully developed yet and have a hard time controlling her ring finger.
Yeah, it look weird. Guess that's by it's not as popular, but while seeing my baby develop, I saw that they developed control over thumb and index, then middle. So, it's the quickest way to teach them to count up 3.
I've started doing it all the time now as well, as it's valid ASL and we have two hard of hearing children, one of which communicates primarily with sign.
I use my index finger and my pinky with my middle finger curling around my ring finger. As a white foreigner, I show them horizontally on the east coast of the US like an E and vertically on the west coast like a W to try to fit in better. ;)